Aluminium alloy



Patented Jan. 3, 1933 UNITED STATES OTTO ms, 01' AACHEN, GERMANY ALUMINIUM ALLOY No Drawing. Application filed December 5, 1929, Serial No. 411,978, and in Germany October 5, 1927. i

- C. and subsequently submitted to a heating treatment between 300 and 50 C. in a barium-chloride bath, which is a solution of a barium-chloride salt.

These variations in tem rature depend less upon the actual'composztion of the alloy than upon the stren h and expansion. Different tempering eats. are selected, as strength, expansion and tempering heaters are dependent upon one another and as it is possib e by suitabl selecting the temperatures, to give the al oy a strength and expansion of a certain value determined by the use of the alloy for the actual constructional purpose.- In the case of an alloy with a nickel content of 1% and a thorium content of 0.2%

. i a temperature of 180 C. .should be chosen.

The contents of the alloy with n the limits in- H i .dicated are necessary in the case of use of the alloy resistin' sea water and atmospheric '7 so influences. T e nickel and thorium contents are absolutely indispensable therefor.

The new alloy is an extremely thin liquid in molten state and surpasses the known aluminium alloys in regard to its possibilities of use as itcan be cast to paper thickness in sand and enables in the most complicated castings an absolutely perfect 'sha e without blowholes or shrinking holes. e strength of the castings made from th s alloy 4 varies according to the thickness of the walls between 16 and 22 kgs. per square millimetre. By treating the alloy according to the refining process indicated the strength of the material is increased. Besides its homogeneous,

fine crystalline grain the alloy is remarkable an extent that the alloy is suitable as mate-" for its extremely high resisting properties against acids, saline solut ons and sea water. These properties ermit of an extensive workin of the alloy 1n cast and rolled form.

e material produced from the alloy prac- 5o. tically does not oxidize, is clean and does not mark. It can be easily rolled and in rolled condition attains a strength of 40 to kgs. per square millimetre with expansions of 11 to 15%. By subsequent compression by rolling 55 and the like the strength of the alloy may be increased to to kgs. per square millimetre. Plates may be rolled from the alloy in any length and width without edge crackingand wlthout soilin the rolls. Of particular importance is the fact that the sore may be repeatedly melted down and the qua 'ty of the material is considerably improved thereby in that it becomes more and more homogeneous. The alloy may be used with great suc- 65. c'ess for splash and chill castings as the thin liquidity allows the most complicated castings .to be made without trouble with an accuracy of 1/100 mm. If 1.5%Tnickel be added to the new alloy the shrinkage is reduced tosuch rial for internal pistons of. combustion en-g gines. With suitable percentages of nickel and thorium the alloy has given excellent re'-' salts. The admixture of thorium increases 15 the critical recrystallization temperature, so v that hot stressed rolled materials may be subjected in work to hi her temperatures without any danger of hot rittleness by reducing the strength properties. 0,

- The alloy prefer bly has the following composition 0.3 to 1.5% nickel, 0.05 to 0.9% thorium, 6.8% binary copper-cerium alloy containing copper and 10% cerium, 0.4 to 0.8% manganese and the remainder. aluminium with the usual commercial iron content tolerances.

A heat treated aluminium alloy consisting of an alloy containing 5% copper, 0.3% nicke1, 0.1% thorium, 6.8% binary copgencerimn alloy containing 90% popper and 1 cerium, havm a. fine crystalline structure and the remain er aluminium quenched from utemper. 5 uture of from 635 to 480 C. to room tempera.- tu're in a. barium chloride bath and subsequently submitted to a. heating treatment between 800 and 50 C. to produce steel hardness. 1 Intestimony whereofIafiixm si ature.

OTTO K 

